This invention relates generally to alternative energy technologies and in particular to rechargeable batteries for vehicles.
A significant amount of research and development resources are being devoted towards alternative energy technologies. Global warming issues driven from the carbon released in the atmosphere from burning of fossil fuels and other green house gases has led to a significant worldwide interest from scientists and researchers to address the issues. Alternative energy technologies like wind, solar, electrochemical, magnetic, geothermal, biomass, nuclear and the like are being pursued aggressively for large scale commercialization to mitigate the impact of fossil fuel based energy resources on climate change as well as over cost of such fuels.
Electrochemical batteries and fuel cells have been considered as most promising energy research area by their supporters. These small and non-polluting devices that produce energy without combustion could help many residential power needs, but their most exciting application is in transportation. These devices are used in the automotive market in hybrid vehicles that have seen a 20 fold increase in their sales from 10,000 units in 2000 to over 200,000 cars in 2005. The key driving force behind the development and the sale of hybrid vehicles is the improvement in fuel efficiency and economy. Hybrid vehicles comprise of both an internal combustion engine and an electric motor which run on gasoline and battery power respectively. Today's commercially available hybrid vehicles use small batteries or fuel cells which can store 1-2 kilowatt-hours of energy. The electric battery power is primarily used for shorter distances with stop and go traffic where the gasoline fuel economy is very low. However, if the battery capacity of the hybrid vehicles is increased to include 6-8 kilowatt-hours of energy storage, the vehicle could operate in an electric-only mode for up to 50 miles. However, development of battery technology for use of such vehicles in electric-only mode for distances larger than 50 miles is considered extremely difficult by leading scientists. This would practically prevent creation of pure electric-only vehicles that give comparable driving range as presently available gasoline vehicles without recharging or refueling.
Today's hybrid vehicles utilize Nickel Metal Hydride (Ni-MH) batteries, however Lithium-ion (Li-ion) batteries can be used to double the energy efficiency and power over Ni-MH batteries. However for pure electric only vehicles at least a doubling of battery capacity over Li-ion batteries is required which is considered a nontrivial undertaking by leading research organizations.
Our inventions show a system of energy storage and charging usable in vehicles and other applications that eliminate the battery capacity and automotive range issues discussed above.